Examining Tradeoffs between High Speed Rail and Air Transportation: An Environmental Analysis of the Northeast Corridor
Professor Joseph Sussman
Regina Clewlow (Teaching Assistant)
The transportation sector is a major source of greenhouse gas emissions, responsible for roughly one-third of CO2 emissions globally, and nearly 50 percent of the increase from 1990 emission levels in the United States. Although aviation is currently responsible for only three percent of greenhouse-gas emissions and five percent of global warming, it is among the fastest growing modes within the transportation sector. In fast, most transportation experts predict that over the next 50 years, general transportation volume will increase and shift towards faster modes - primarily aviation (Schafer, 2000). Under business-as-usual scenarios, CO2 emissions from global aviation are expected to increase by 300 percent over the next 40 years (IEA, 2008b).
In many parts of the world, including Europe, Japan, and Korea, high-speed rail has served as an effective substitute for air transportation, and is often promoted as a more environmentally friendly alternative. One study estimates that the CO2 emissions for high speed rail range from 4.011 to 27.515 per kilometer, while CO2 emissions for air transportation are higher at 99.8 to 153.9 per kilometer (Janic, 2003). However, more recent studies indicate that the environmental savings of high-speed rail depend significantly on the ridership levels, partly due to the environmental impacts associated with building rail infrastructure (Chester and Horvath, 2009).
The Department of Transportation (DOT) has designated ten high-speed rail corridors for development in the United States, and many additional corridor extensions. In 2010, the DOT awarded $8 billion of funding through the American Recovery and Reinvestment Act to states to support high-speed rail infrastructure, including the proposed California corridor and improvements to the Northeast Corridor (NEC).
Given the significant growth anticipated in demand for non-road transportation (i.e. air transportation and high-speed rail), we would like to explore future projections of intercity passenger demand and their resulting environmental impacts.
This project team will perform an analysis of high-speed rail and air transportation in the Northeast Corridor. The team will examine future projections of demand for high-speed rail and air transportation, analyze the associated CO2 emissions of this demand, and estimate emissions associated with air and rail infrastructure in the Northeast. The NEC is the only existing high-speed rail corridor in the U.S., where Amtrak’s Acela Express provides service between Boston and Washington, DC (via New York, Philadelphia and Baltimore). Although the Acela Express averages only 68 mph for the Boston to DC journey, it is capable of reaching speeds of 150 mph and provides Boston-NYC service in 3hr31min and NYC-DC service in 2hr45min (NEC, 2010). The NEC Infrastructure Master Plan outlines proposed improvements for this densely populated corridor of the United States.
Expanding on previous analyses of demand and environmental impacts of air and rail transportation in this region, the project team will conduct an uncertainty analysis of rail and air demand, as well as a more complete environmental analysis of the CO2 emissions for these two modes. The end result will be a more robust understanding of future transportation scenarios in the U.S. Northeast.
Through this project, students will:
- Identify uncertainties associated with the demand of high-speed rail and air transportation in the Northeast corridor. Uncertainty analysis will include identifying the key sources of uncertainty in the system, and quantifying their potential range of values. Given these uncertainties, students will develop potential scenarios for future demand and HSR and air transportation in the Northeast Corridor.
- Using lifecycle emissions analysis (LCA) methods, the team will estimate the CO2 emissions associated with different demand scenarios identified in Part 1, as well as the emissions of the required infrastructure improvements.
- Identify sources of feedback, delay, and non-linear behavior associated with high-speed rail and air transportation demand and environmental impacts. Students will develop a schematic of a potential system dynamic model for this system.
- Develop alternative network structures for high-speed rail and air transportation in the Northeast Corridor. There are numerous high-speed rail network designs that could be proposed for the Northeast Corridor - all with different levels of feasibility, different demand scenarios, and implementation challenges. The team will design an integrated transportation network structure for high-speed rail and air transportation in the Northeast.